<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        p{
            color: red;
            font-size: 30px;
        }
    </style>
</head>
<body>
    <p style="color: rgb(9, 255, 0); font-size: 20x;">
        hello world
    </p>
    <p>
        hello world
    </p>
    <h1 style="color: blue; font-size: 15px;">你好！世界</h1>
</body>
</html>